Transceiver, modulation integrated circuit, and rfid reader/writer

A transceiver, which selectively transmits a modulated wave and a non-modulated wave to the outside, and receives a response signal from the outside, comprising:

• an oscillator generating a predetermined carrier wave,
• a modulator being inputted with a baseband signal produced according to data, and modulating the carrier wave generated by the oscillator with the baseband signal to generate a modulated wave,
• a transmission unit transmitting the modulated wave modulated by the modulator or a non-modulated wave, and
• an interruption unit interrupting input of the baseband signal into the modulator when the transmission unit transmits the non-modulated wave.

A modulation integrated circuit, which selectively transmits a modulated wave and a non-modulated wave to the outside, comprising:

• a carrier wave input terminal for inputting the carrier wave from the outside,
• a modulator for modulating the carrier wave inputted from the carrier wave input terminal,
• an output terminal for outputting the modulated wave modulated by the modulator, or the non-modulated wave, and
• a connection unit connecting the carrier wave inputted from the carrier wave input terminal to the output terminal while passing through the modulator when the modulated wave is outputted, and directly connecting the carrier wave to the output terminal without passing through the modulator when the non-modulated wave is outputted, according to a switching signal from the outside.

A modulation integrated circuit, which selectively transmits a modulated wave and a non-modulated wave to the outside, comprising:

• an input terminal being inputted with a baseband signal produced according to data from the outside,
• a modulator being provided in a manner connectable to the input terminal, and modulating the carrier wave inputted from the outside with the baseband signal to generate the modulated wave,
• an output terminal for outputting the modulated wave modulated by the modulator, or the non-modulated wave, and
• an interruption unit interrupting connection of the modulator to the input terminal when the non-modulated wave is outputted from the output terminal, according to a switching signal from the outside.